/*
 * This file is in the public domain, so clarified as of
 * 2006-07-17 by Arthur David Olson.
 *
 * IDENTIFICATION
 *	  src/common/timezone/zic.cpp
 */

#include "postgres_fe.h"

#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
#include <limits.h>
#include <locale.h>

extern int optind;
extern char* optarg;

#include "private.h"
#include "pgtz.h"
#include "tzfile.h"

#define ZIC_VERSION '2'

typedef int64 zic_t;

#ifndef ZIC_MAX_ABBR_LEN_WO_WARN
#define ZIC_MAX_ABBR_LEN_WO_WARN 6
#endif /* !defined ZIC_MAX_ABBR_LEN_WO_WARN */

#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif

#ifndef WIN32
#ifdef S_IRUSR
#define MKDIR_UMASK (S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH)
#else
#define MKDIR_UMASK 0755
#endif
#endif

static char elsieid[] = "@(#)zic.c	8.20";

/*
 * On some ancient hosts, predicates like `isspace(C)' are defined
 * only if isascii(C) || C == EOF. Modern hosts obey the C Standard,
 * which says they are defined only if C == ((unsigned char) C) || C == EOF.
 * Neither the C Standard nor Posix require that `isascii' exist.
 * For portability, we check both ancient and modern requirements.
 * If isascii is not defined, the isascii check succeeds trivially.
 */
#include <ctype.h>
#ifndef isascii
#define isascii(x) 1
#endif

#define OFFSET_STRLEN_MAXIMUM (7 + INT_STRLEN_MAXIMUM(long))
#define RULE_STRLEN_MAXIMUM 8 /* "Mdd.dd.d" */

#define end(cp) (strchr((cp), '\0'))
#define UTC_OFFSET_MAX_NUM 2147483647L

struct rule {
    const char* r_filename;
    int r_linenum;
    const char* r_name;

    int r_loyear; /* for example, 1986 */
    int r_hiyear; /* for example, 1986 */
    const char* r_yrtype;
    int r_lowasnum;
    int r_hiwasnum;

    int r_month; /* 0..11 */

    int r_dycode; /* see below */
    int r_dayofmonth;
    int r_wday;

    long r_tod;     /* time from midnight */
    int r_todisstd; /* above is standard time if TRUE */
    /* or wall clock time if FALSE */
    int r_todisgmt; /* above is GMT if TRUE */
    /* or local time if FALSE */
    long r_stdoff;         /* offset from standard time */
    const char* r_abbrvar; /* variable part of abbreviation */

    int r_todo;   /* a rule to do (used in outzone) */
    zic_t r_temp; /* used in outzone */
};

/*
 *	r_dycode		r_dayofmonth	r_wday
 */

#define DC_DOM 0 /* 1..31 */    /* unused */
#define DC_DOWGEQ 1 /* 1..31 */ /* 0..6 (Sun..Sat) */
#define DC_DOWLEQ 2 /* 1..31 */ /* 0..6 (Sun..Sat) */

struct zone {
    const char* z_filename;
    int z_linenum;

    const char* z_name;
    long z_gmtoff;
    const char* z_rule;
    const char* z_format;

    long z_stdoff;

    struct rule* z_rules;
    int z_nrules;

    struct rule z_untilrule;
    zic_t z_untiltime;
};

extern int link(const char* fromname, const char* toname);
static void addtt(const pg_time_t starttime, int type);
static int addtype(long gmtoff, const char* abbr, int isdst, int ttisstd, int ttisgmt);
static void leapadd(const pg_time_t t, int positive, int rolling, int count);
static void adjleap(void);
static void associate(void);
static int ciequal(const char* ap, const char* bp);
static void convert(long val, char* buf);
static void dolink(const char* fromfile, const char* tofile);
static void doabbr(char* abbr, int abbr_size, const char* format, const char* letters, int isdst, int doquotes);
static void eat(const char* name, int num);
static void eats(const char* name, int num, const char* rname, int rnum);
static long eitol(int i);
static void error(const char* message);
static char** getfields(char* buf);
static long gethms(const char* string, const char* errstrng, int signable);
static void infile(const char* filename);
static void inleap(const char** fields, int nfields);
static void inlink(const char** fields, int nfields);
static void inrule(const char** fields, int nfields);
static int inzcont(char** fields, int nfields);
static int inzone(char** fields, int nfields);
static int inzsub(char** fields, int nfields, int iscont);
static int itsabbr(const char* abbr, const char* word);
static int itsdir(const char* name);
static int lowerit(int c);
static char* memcheck(const char* tocheck);
static int mkdirs(const char* filename);
static void newabbr(const char* abbr);
static long oadd(long t1, long t2);
static void outzone(const struct zone* zp, int ntzones);
static void puttzcode(long code, FILE* fp);
static int rcomp(const void* leftp, const void* rightp);
static pg_time_t rpytime(const struct rule* rp, int wantedy);
static void rulesub(struct rule* rp, const char* loyearp, const char* hiyearp, const char* typep, const char* monthp,
    const char* dayp, const char* timep);
static void setboundaries(void);
static pg_time_t tadd(const pg_time_t t1, long t2);
static void usage(FILE* stream, int status);
static void writezone(const char* name, const char* string);
static int yearistype(int year, const char* type);

static int charcnt;
static int errors;
static const char* filename;
static int leapcnt;
static int leapseen;
static int leapminyear;
static int leapmaxyear;
static int linenum;
static int max_abbrvar_len;
static int max_format_len;
static zic_t max_time;
static int max_year;
static zic_t min_time;
static int min_year;
static int noise;
static const char* rfilename;
static int rlinenum;
static const char* progname;
static int timecnt;
static int typecnt;

/*
 * Line codes.
 */
#define LC_RULE 0
#define LC_ZONE 1
#define LC_LINK 2
#define LC_LEAP 3

/*
 * Which fields are which on a Zone line.
 */
#define ZF_NAME 1
#define ZF_GMTOFF 2
#define ZF_RULE 3
#define ZF_FORMAT 4
#define ZF_TILYEAR 5
#define ZF_TILMONTH 6
#define ZF_TILDAY 7
#define ZF_TILTIME 8
#define ZONE_MINFIELDS 5
#define ZONE_MAXFIELDS 9

/*
 * Which fields are which on a Zone continuation line.
 */
#define ZFC_GMTOFF 0
#define ZFC_RULE 1
#define ZFC_FORMAT 2
#define ZFC_TILYEAR 3
#define ZFC_TILMONTH 4
#define ZFC_TILDAY 5
#define ZFC_TILTIME 6
#define ZONEC_MINFIELDS 3
#define ZONEC_MAXFIELDS 7

/*
 * Which files are which on a Rule line.
 */
#define RF_NAME 1
#define RF_LOYEAR 2
#define RF_HIYEAR 3
#define RF_COMMAND 4
#define RF_MONTH 5
#define RF_DAY 6
#define RF_TOD 7
#define RF_STDOFF 8
#define RF_ABBRVAR 9
#define RULE_FIELDS 10

/*
 * Which fields are which on a Link line.
 */
#define LF_FROM 1
#define LF_TO 2
#define LINK_FIELDS 3

/*
 * Which fields are which on a Leap line.
 */
#define LP_YEAR 1
#define LP_MONTH 2
#define LP_DAY 3
#define LP_TIME 4
#define LP_CORR 5
#define LP_ROLL 6
#define LEAP_FIELDS 7

/*
 * Year synonyms.
 */
#define YR_MINIMUM 0
#define YR_MAXIMUM 1
#define YR_ONLY 2

static struct rule* rules;
static int nrules; /* number of rules */

static struct zone* zones;
static int nzones; /* number of zones */

struct link {
    const char* l_filename;
    int l_linenum;
    const char* l_from;
    const char* l_to;
};

static struct link* links;
static int nlinks;

struct lookup {
    const char* l_word;
    const int l_value;
};

static struct lookup const* byword(const char* string, const struct lookup* lp);

static struct lookup const line_codes[] = {
    {"Rule", LC_RULE}, {"Zone", LC_ZONE}, {"Link", LC_LINK}, {"Leap", LC_LEAP}, {NULL, 0}};

static struct lookup const mon_names[] = {{"January", TM_JANUARY},
    {"February", TM_FEBRUARY},
    {"March", TM_MARCH},
    {"April", TM_APRIL},
    {"May", TM_MAY},
    {"June", TM_JUNE},
    {"July", TM_JULY},
    {"August", TM_AUGUST},
    {"September", TM_SEPTEMBER},
    {"October", TM_OCTOBER},
    {"November", TM_NOVEMBER},
    {"December", TM_DECEMBER},
    {NULL, 0}};

static struct lookup const wday_names[] = {{"Sunday", TM_SUNDAY},
    {"Monday", TM_MONDAY},
    {"Tuesday", TM_TUESDAY},
    {"Wednesday", TM_WEDNESDAY},
    {"Thursday", TM_THURSDAY},
    {"Friday", TM_FRIDAY},
    {"Saturday", TM_SATURDAY},
    {NULL, 0}};

static struct lookup const lasts[] = {{"last-Sunday", TM_SUNDAY},
    {"last-Monday", TM_MONDAY},
    {"last-Tuesday", TM_TUESDAY},
    {"last-Wednesday", TM_WEDNESDAY},
    {"last-Thursday", TM_THURSDAY},
    {"last-Friday", TM_FRIDAY},
    {"last-Saturday", TM_SATURDAY},
    {NULL, 0}};

static struct lookup const begin_years[] = {{"minimum", YR_MINIMUM}, {"maximum", YR_MAXIMUM}, {NULL, 0}};

static struct lookup const end_years[] = {
    {"minimum", YR_MINIMUM}, {"maximum", YR_MAXIMUM}, {"only", YR_ONLY}, {NULL, 0}};

static struct lookup const leap_types[] = {{"Rolling", TRUE}, {"Stationary", FALSE}, {NULL, 0}};

static const int len_months[2][MONSPERYEAR] = {
    {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}};

static const int len_years[2] = {DAYSPERNYEAR, DAYSPERLYEAR};

static struct attype {
    zic_t at;
    unsigned char type;
} attypes[TZ_MAX_TIMES];
static long gmtoffs[TZ_MAX_TYPES];
static char isdsts[TZ_MAX_TYPES];
static unsigned char abbrinds[TZ_MAX_TYPES];
static char ttisstds[TZ_MAX_TYPES];
static char ttisgmts[TZ_MAX_TYPES];
static char chars[TZ_MAX_CHARS];
static zic_t trans[TZ_MAX_LEAPS];
static long corr[TZ_MAX_LEAPS];
static char roll[TZ_MAX_LEAPS];

/*
 * Memory allocation.
 */
static char* memcheck(const char* ptr)
{
    if (ptr == NULL) {
        const char* e = gs_strerror(errno);

        (void)fprintf(stderr, _("%s: Memory exhausted: %s\n"), progname, e);
        exit(EXIT_FAILURE);
    }
    return (char*)ptr;
}

#define emalloc(size) memcheck(imalloc(size))
#define erealloc(ptr, size) memcheck((char*)irealloc((ptr), (size)))
#define ecpyalloc(ptr) memcheck(icpyalloc(ptr))
#define ecatalloc(oldp, newp) memcheck(icatalloc((oldp), (newp)))

/*
 * Error handling.
 */
static void eats(const char* name, int num, const char* rname, int rnum)
{
    filename = name;
    linenum = num;
    rfilename = rname;
    rlinenum = rnum;
}

static void eat(const char* name, int num)
{
    eats(name, num, (char*)NULL, -1);
}

static void error(const char* string)
{
    /*
     * Match the format of "cc" to allow sh users to  zic ... 2>&1 | error -t
     * "*" -v on BSD systems.
     */
    (void)fprintf(stderr, _("\"%s\", line %d: %s"), filename, linenum, string);
    if (rfilename != NULL) {
        (void)fprintf(stderr, _(" (rule from \"%s\", line %d)"), rfilename, rlinenum);
    }
    (void)fprintf(stderr, "\n");
    ++errors;
}

static void warning(const char* string)
{
    char* cp = NULL;

    cp = ecpyalloc(_("warning: "));
    cp = ecatalloc(cp, string);
    error(cp);
    ifree(cp);
    cp = NULL;
    --errors;
}

static void usage(FILE* stream, int status)
{
    (void)fprintf(stream,
        _("%s: usage is %s \
[ --version ] [ --help ] [ -v ] [ -l localtime ] [ -p posixrules ] \\\n\
\t[ -d directory ] [ -L leapseconds ] [ -y yearistype ] [ filename ... ]\n\
\n\
Report bugs to tz@elsie.nci.nih.gov.\n"),
        progname,
        progname);
    exit(status);
}

static const char* psxrules;
static const char* lcltime;
static const char* directory;
static const char* leapsec;
static const char* yitcommand;

int main(int argc, char* argv[])
{
    int i;
    int j;
    int c;

#ifndef WIN32
    (void)umask(umask(S_IWGRP | S_IWOTH) | (S_IWGRP | S_IWOTH));
#endif /* !WIN32 */
    progname = argv[0];
    if (TYPE_BIT(zic_t) < 64) {
        (void)fprintf(stderr, "%s: %s\n", progname, _("wild compilation-time specification of zic_t"));
        exit(EXIT_FAILURE);
    }
    for (i = 1; i < argc; ++i) {
        if (strcmp(argv[i], "--version") == 0) {
            (void)printf("%s\n", elsieid);
            exit(EXIT_SUCCESS);
        } else if (strcmp(argv[i], "--help") == 0) {
            usage(stdout, EXIT_SUCCESS);
        }
    }
    while ((c = getopt(argc, argv, "d:l:p:L:vsy:")) != EOF && c != -1) {
        switch (c) {
            default:
                usage(stderr, EXIT_FAILURE);
            case 'd':
                if (directory == NULL) {
                    directory = optarg;
                } else {
                    (void)fprintf(stderr, _("%s: More than one -d option specified\n"), progname);
                    exit(EXIT_FAILURE);
                }
                break;
            case 'l':
                if (lcltime == NULL) {
                    lcltime = optarg;
                } else {
                    (void)fprintf(stderr, _("%s: More than one -l option specified\n"), progname);
                    exit(EXIT_FAILURE);
                }
                break;
            case 'p':
                if (psxrules == NULL) {
                    psxrules = optarg;
                } else {
                    (void)fprintf(stderr, _("%s: More than one -p option specified\n"), progname);
                    exit(EXIT_FAILURE);
                }
                break;
            case 'y':
                if (yitcommand == NULL) {
                    yitcommand = optarg;
                } else {
                    (void)fprintf(stderr, _("%s: More than one -y option specified\n"), progname);
                    exit(EXIT_FAILURE);
                }
                break;
            case 'L':
                if (leapsec == NULL) {
                    leapsec = optarg;
                } else {
                    (void)fprintf(stderr, _("%s: More than one -L option specified\n"), progname);
                    exit(EXIT_FAILURE);
                }
                break;
            case 'v':
                noise = TRUE;
                break;
            case 's':
                (void)printf("%s: -s ignored\n", progname);
                break;
        }
    }
    if (optind == argc - 1 && strcmp(argv[optind], "=") == 0) {
        usage(stderr, EXIT_FAILURE); /* usage message by request */
    }
    if (directory == NULL) {
        directory = "data";
    }
    if (yitcommand == NULL) {
        yitcommand = "yearistype";
    }

    setboundaries();

    if (optind < argc && leapsec != NULL) {
        infile(leapsec);
        adjleap();
    }

    for (i = optind; i < argc; ++i) {
        infile(argv[i]);
    }
    if (errors) {
        exit(EXIT_FAILURE);
    }
    associate();
    for (i = 0; i < nzones; i = j) {
        /*
         * Find the next non-continuation zone entry.
         */
        for (j = i + 1; j < nzones && zones[j].z_name == NULL; ++j) {
            continue;
        }
        outzone(&zones[i], j - i);
    }

    /*
     * Make links.
     */
    for (i = 0; i < nlinks; ++i) {
        eat(links[i].l_filename, links[i].l_linenum);
        dolink(links[i].l_from, links[i].l_to);
        if (noise) {
            for (j = 0; j < nlinks; ++j) {
                if (strcmp(links[i].l_to, links[j].l_from) == 0) {
                    warning(_("link to link"));
                }
            }
        }
    }
    if (lcltime != NULL) {
        eat("command line", 1);
        dolink(lcltime, TZDEFAULT);
    }
    if (psxrules != NULL) {
        eat("command line", 1);
        dolink(psxrules, TZDEFRULES);
    }
    return (errors == 0) ? EXIT_SUCCESS : EXIT_FAILURE;
}

static void dolink(const char* fromfield, const char* tofield)
{
    char* fromname = NULL;
    char* toname = NULL;

    if (fromfield[0] == '/') {
        fromname = ecpyalloc(fromfield);
    } else {
        fromname = ecpyalloc(directory);
        fromname = ecatalloc(fromname, "/");
        fromname = ecatalloc(fromname, fromfield);
    }
    if (tofield[0] == '/') {
        toname = ecpyalloc(tofield);
    } else {
        toname = ecpyalloc(directory);
        toname = ecatalloc(toname, "/");
        toname = ecatalloc(toname, tofield);
    }

    /*
     * We get to be careful here since there's a fair chance of root running
     * us.
     */
    if (!itsdir(toname)) {
        (void)remove(toname);
    }
    if (link(fromname, toname) != 0) {
        int result;

        if (mkdirs(toname) != 0) {
            exit(EXIT_FAILURE);
        }

        result = link(fromname, toname);
#ifdef HAVE_SYMLINK
        if (result != 0 && access(fromname, F_OK) == 0 && !itsdir(fromname)) {
            const char* s = tofield;
            char* symlinkcontents = NULL;

            while ((s = strchr(s + 1, '/')) != NULL) {
                symlinkcontents = ecatalloc(symlinkcontents, "../");
            }
            symlinkcontents = ecatalloc(symlinkcontents, fromfield);

            result = symlink(symlinkcontents, toname);
            if (result == 0) {
                warning(_("hard link failed, symbolic link used"));
            }
            ifree(symlinkcontents);
            symlinkcontents = NULL;
        }
#endif
        if (result != 0) {
            const char* e = gs_strerror(errno);

            (void)fprintf(stderr, _("%s: Cannot link from %s to %s: %s\n"), progname, fromname, toname, e);
            exit(EXIT_FAILURE);
        }
    }
    ifree(fromname);
    ifree(toname);
    fromname = NULL;
    toname = NULL;
}

#define TIME_T_BITS_IN_FILE 64

static void setboundaries(void)
{
    int i;

    min_time = -1;
    for (i = 0; i < TIME_T_BITS_IN_FILE - 1; ++i) {
        min_time *= 2;
    }
    max_time = -(min_time + 1);
}

static int itsdir(const char* name)
{
    char* myname = NULL;
    int accres;

    myname = ecpyalloc(name);
    myname = ecatalloc(myname, "/.");
    accres = access(myname, F_OK);
    ifree(myname);
    myname = NULL;
    return accres == 0;
}

/*
 * Associate sets of rules with zones.
 */

/*
 * Sort by rule name.
 */

static int rcomp(const void* cp1, const void* cp2)
{
    return strcmp(((const struct rule*)cp1)->r_name, ((const struct rule*)cp2)->r_name);
}

static void associate(void)
{
    struct zone* zp = NULL;
    struct rule* rp = NULL;
    int base, out;
    int i, j;

    if (nrules != 0) {
        (void)qsort((void*)rules, (size_t)(unsigned int)nrules, (size_t)sizeof *rules, rcomp);
        for (i = 0; i < nrules - 1; ++i) {
            if (strcmp(rules[i].r_name, rules[i + 1].r_name) != 0) {
                continue;
            }
            if (strcmp(rules[i].r_filename, rules[i + 1].r_filename) == 0) {
                continue;
            }
            eat(rules[i].r_filename, rules[i].r_linenum);
            warning(_("same rule name in multiple files"));
            eat(rules[i + 1].r_filename, rules[i + 1].r_linenum);
            warning(_("same rule name in multiple files"));
            for (j = i + 2; j < nrules; ++j) {
                if (strcmp(rules[i].r_name, rules[j].r_name) != 0) {
                    break;
                }
                if (strcmp(rules[i].r_filename, rules[j].r_filename) == 0) {
                    continue;
                }
                if (strcmp(rules[i + 1].r_filename, rules[j].r_filename) == 0) {
                    continue;
                }
                break;
            }
            i = j - 1;
        }
    }
    for (i = 0; i < nzones; ++i) {
        zp = &zones[i];
        zp->z_rules = NULL;
        zp->z_nrules = 0;
    }
    for (base = 0; base < nrules; base = out) {
        rp = &rules[base];
        for (out = base + 1; out < nrules; ++out) {
            if (strcmp(rp->r_name, rules[out].r_name) != 0) {
                break;
            }
        }
        for (i = 0; i < nzones; ++i) {
            zp = &zones[i];
            if (strcmp(zp->z_rule, rp->r_name) != 0) {
                continue;
            }
            zp->z_rules = rp;
            zp->z_nrules = out - base;
        }
    }
    for (i = 0; i < nzones; ++i) {
        zp = &zones[i];
        if (zp->z_nrules == 0) {
            /*
             * Maybe we have a local standard time offset.
             */
            eat(zp->z_filename, zp->z_linenum);
            zp->z_stdoff = gethms(zp->z_rule, _("unruly zone"), TRUE);

            /*
             * Note, though, that if there's no rule, a '%s' in the format is
             * a bad thing.
             */
            if (strchr(zp->z_format, '%') != NULL) {
                error(_("percent signs in ruleless zone"));
            }
        }
    }
    if (errors) {
        exit(EXIT_FAILURE);
    }
}

static void infile(const char* name)
{
    FILE* fp = NULL;
    char** fields;
    char* cp = NULL;
    const struct lookup* lp = NULL;
    int nfields;
    int wantcont;
    int num;
    char buf[BUFSIZ];

    if (strcmp(name, "-") == 0) {
        name = _("standard input");
        fp = stdin;
    } else if ((fp = fopen(name, "r")) == NULL) {
        const char* e = gs_strerror(errno);

        (void)fprintf(stderr, _("%s: Cannot open %s: %s\n"), progname, name, e);
        exit(EXIT_FAILURE);
    }
    wantcont = FALSE;
    for (num = 1;; ++num) {
        eat(name, num);
        if (fgets(buf, (int)sizeof buf, fp) != buf) {
            break;
        }
        cp = strchr(buf, '\n');
        if (cp == NULL) {
            error(_("line too long"));
            exit(EXIT_FAILURE);
        }
        *cp = '\0';
        fields = getfields(buf);
        nfields = 0;
        while (fields[nfields] != NULL) {
            static char nada;

            if (strcmp(fields[nfields], "-") == 0) {
                fields[nfields] = &nada;
            }
            ++nfields;
        }
        if (nfields == 0) {
            /* nothing to do */
        } else if (wantcont) {
            wantcont = inzcont(fields, nfields);
        } else {
            lp = byword(fields[0], line_codes);
            if (lp == NULL) {
                error(_("input line of unknown type"));
            } else {
                switch ((int)(lp->l_value)) {
                    case LC_RULE:
                        inrule((const char**)fields, nfields);
                        wantcont = FALSE;
                        break;
                    case LC_ZONE:
                        wantcont = inzone(fields, nfields);
                        break;
                    case LC_LINK:
                        inlink((const char**)fields, nfields);
                        wantcont = FALSE;
                        break;
                    case LC_LEAP:
                        if (name != leapsec) {
                            (void)fprintf(stderr, _("%s: Leap line in non leap seconds file %s\n"), progname, name);
                        } else {
                            inleap((const char**)fields, nfields);
                        }
                        wantcont = FALSE;
                        break;
                    default: /* "cannot happen" */
                        (void)fprintf(stderr, _("%s: panic: Invalid l_value %d\n"), progname, lp->l_value);
                        exit(EXIT_FAILURE);
                }
            }
        }
        ifree((char*)fields);
    }
    if (ferror(fp)) {
        (void)fprintf(stderr, _("%s: Error reading %s\n"), progname, filename);
        exit(EXIT_FAILURE);
    }
    if (fp != stdin && fclose(fp)) {
        const char* e = gs_strerror(errno);

        (void)fprintf(stderr, _("%s: Error closing %s: %s\n"), progname, filename, e);
        exit(EXIT_FAILURE);
    }
    if (wantcont) {
        error(_("expected continuation line not found"));
    }
}

/* ----------
 * Convert a string of one of the forms
 *	h	-h	hh:mm	-hh:mm	hh:mm:ss	-hh:mm:ss
 * into a number of seconds.
 * A null string maps to zero.
 * Call error with errstring and return zero on errors.
 * ----------
 */
static long gethms(const char* string, const char* errstring, int signable)
{
    long hh;
    int mm, ss, sign;

    if (string == NULL || *string == '\0') {
        return 0;
    }
    if (!signable) {
        sign = 1;
    } else if (*string == '-') {
        sign = -1;
        ++string;
    } else {
        sign = 1;
    }
    if (sscanf_s(string, scheck(string, "%ld"), &hh) == 1)
        mm = ss = 0;
    else if (sscanf_s(string, scheck(string, "%ld:%d"), &hh, &mm) == 2)
        ss = 0;
    else if (sscanf_s(string, scheck(string, "%ld:%d:%d"), &hh, &mm, &ss) != 3) {
        error(errstring);
        return 0;
    }
    if (hh < 0 || mm < 0 || mm >= MINSPERHOUR || ss < 0 || ss > SECSPERMIN) {
        error(errstring);
        return 0;
    }
    if (LONG_MAX / SECSPERHOUR < hh) {
        error(_("time overflow"));
        return 0;
    }
    if (noise && hh == HOURSPERDAY && mm == 0 && ss == 0) {
        warning(_("24:00 not handled by pre-1998 versions of zic"));
    }
    if (noise && (hh > HOURSPERDAY || (hh == HOURSPERDAY && (mm != 0 || ss != 0)))) {
        warning(_("values over 24 hours not handled by pre-2007 versions of zic"));
    }
    return oadd(eitol(sign) * hh * eitol(SECSPERHOUR), eitol(sign) * (eitol(mm) * eitol(SECSPERMIN) + eitol(ss)));
}

static void inrule(const char** fields, int nfields)
{
    static struct rule r;

    if (nfields != RULE_FIELDS) {
        error(_("wrong number of fields on Rule line"));
        return;
    }
    if (*fields[RF_NAME] == '\0') {
        error(_("nameless rule"));
        return;
    }
    r.r_filename = filename;
    r.r_linenum = linenum;
    r.r_stdoff = gethms(fields[RF_STDOFF], _("invalid saved time"), TRUE);
    rulesub(
        &r, fields[RF_LOYEAR], fields[RF_HIYEAR], fields[RF_COMMAND], fields[RF_MONTH], fields[RF_DAY], fields[RF_TOD]);
    r.r_name = ecpyalloc(fields[RF_NAME]);
    r.r_abbrvar = ecpyalloc(fields[RF_ABBRVAR]);
    if ((size_t)(unsigned int)max_abbrvar_len < strlen(r.r_abbrvar)) {
        max_abbrvar_len = strlen(r.r_abbrvar);
    }
    rules = (struct rule*)(void*)erealloc((char*)rules, (int)((nrules + 1) * sizeof *rules));
    rules[nrules++] = r;
}

static int inzone(char** fields, int nfields)
{
    int i;
    static THR_LOCAL char* buf = NULL;

    if (nfields < ZONE_MINFIELDS || nfields > ZONE_MAXFIELDS) {
        error(_("wrong number of fields on Zone line"));
        return FALSE;
    }
    if (strcmp(fields[ZF_NAME], TZDEFAULT) == 0 && lcltime != NULL) {
        buf = erealloc(buf, (int)(132 + strlen(TZDEFAULT)));
        (void)sprintf(buf, _("\"Zone %s\" line and -l option are mutually exclusive"), TZDEFAULT);
        error(buf);
        return FALSE;
    }
    if (strcmp(fields[ZF_NAME], TZDEFRULES) == 0 && psxrules != NULL) {
        buf = erealloc(buf, (int)(132 + strlen(TZDEFRULES)));
        (void)sprintf(buf, _("\"Zone %s\" line and -p option are mutually exclusive"), TZDEFRULES);
        error(buf);
        return FALSE;
    }
    for (i = 0; i < nzones; ++i) {
        if (zones[i].z_name != NULL && strcmp(zones[i].z_name, fields[ZF_NAME]) == 0) {
            buf = erealloc(buf, (int)(132 + strlen(fields[ZF_NAME]) + strlen(zones[i].z_filename)));
            (void)sprintf(buf,
                _("duplicate zone name %s (file \"%s\", line %d)"),
                fields[ZF_NAME],
                zones[i].z_filename,
                zones[i].z_linenum);
            error(buf);
            return FALSE;
        }
    }
    return inzsub(fields, nfields, FALSE);
}

static int inzcont(char** fields, int nfields)
{
    if (nfields < ZONEC_MINFIELDS || nfields > ZONEC_MAXFIELDS) {
        error(_("wrong number of fields on Zone continuation line"));
        return FALSE;
    }
    return inzsub(fields, nfields, TRUE);
}

static int inzsub(char** fields, int nfields, int iscont)
{
    char* cp = NULL;
    static struct zone z;
    int i_gmtoff, i_rule, i_format;
    int i_untilyear, i_untilmonth;
    int i_untilday, i_untiltime;
    int hasuntil;

    if (iscont) {
        i_gmtoff = ZFC_GMTOFF;
        i_rule = ZFC_RULE;
        i_format = ZFC_FORMAT;
        i_untilyear = ZFC_TILYEAR;
        i_untilmonth = ZFC_TILMONTH;
        i_untilday = ZFC_TILDAY;
        i_untiltime = ZFC_TILTIME;
        z.z_name = NULL;
    } else {
        i_gmtoff = ZF_GMTOFF;
        i_rule = ZF_RULE;
        i_format = ZF_FORMAT;
        i_untilyear = ZF_TILYEAR;
        i_untilmonth = ZF_TILMONTH;
        i_untilday = ZF_TILDAY;
        i_untiltime = ZF_TILTIME;
        z.z_name = ecpyalloc(fields[ZF_NAME]);
    }
    z.z_filename = filename;
    z.z_linenum = linenum;
    z.z_gmtoff = gethms(fields[i_gmtoff], _("invalid UTC offset"), TRUE);
    if ((cp = strchr(fields[i_format], '%')) != NULL) {
        if (*++cp != 's' || strchr(cp, '%') != NULL) {
            error(_("invalid abbreviation format"));
            return FALSE;
        }
    }
    z.z_rule = ecpyalloc(fields[i_rule]);
    z.z_format = ecpyalloc(fields[i_format]);
    if ((size_t)(unsigned int)max_format_len < strlen(z.z_format)) {
        max_format_len = strlen(z.z_format);
    }
    hasuntil = nfields > i_untilyear;
    if (hasuntil) {
        z.z_untilrule.r_filename = filename;
        z.z_untilrule.r_linenum = linenum;
        rulesub(&z.z_untilrule,
            fields[i_untilyear],
            "only",
            "",
            (nfields > i_untilmonth) ? fields[i_untilmonth] : "Jan",
            (nfields > i_untilday) ? fields[i_untilday] : "1",
            (nfields > i_untiltime) ? fields[i_untiltime] : "0");
        z.z_untiltime = rpytime(&z.z_untilrule, z.z_untilrule.r_loyear);
        if (iscont && nzones > 0 && z.z_untiltime > min_time && z.z_untiltime < max_time &&
            zones[nzones - 1].z_untiltime > min_time && zones[nzones - 1].z_untiltime < max_time &&
            zones[nzones - 1].z_untiltime >= z.z_untiltime) {
            error(_("Zone continuation line end time is not after end time of previous line"));
            return FALSE;
        }
    }
    zones = (struct zone*)(void*)erealloc((char*)zones, (int)((nzones + 1) * sizeof *zones));
    zones[nzones++] = z;

    /*
     * If there was an UNTIL field on this line, there's more information
     * about the zone on the next line.
     */
    return hasuntil;
}

static void inleap(const char** fields, int nfields)
{
    const char* cp = NULL;
    const struct lookup* lp = NULL;
    int i, j;
    int year, month, day;
    long dayoff, tod;
    zic_t t;

    if (nfields != LEAP_FIELDS) {
        error(_("wrong number of fields on Leap line"));
        return;
    }
    dayoff = 0;
    cp = fields[LP_YEAR];
    if (sscanf_s(cp, scheck(cp, "%d"), &year) != 1) {
        /*
         * Leapin' Lizards!
         */
        error(_("invalid leaping year"));
        return;
    }
    if (!leapseen || leapmaxyear < year) {
        leapmaxyear = year;
    }
    if (!leapseen || leapminyear > year) {
        leapminyear = year;
    }
    leapseen = TRUE;
    j = EPOCH_YEAR;
    while (j != year) {
        if (year > j) {
            i = len_years[isleap(j)];
            ++j;
        } else {
            --j;
            i = -len_years[isleap(j)];
        }
        dayoff = oadd(dayoff, eitol(i));
    }
    if ((lp = byword(fields[LP_MONTH], mon_names)) == NULL) {
        error(_("invalid month name"));
        return;
    }
    month = lp->l_value;
    j = TM_JANUARY;
    while (j != month) {
        i = len_months[isleap(year)][j];
        dayoff = oadd(dayoff, eitol(i));
        ++j;
    }
    cp = fields[LP_DAY];
    if (sscanf_s(cp, scheck(cp, "%d"), &day) != 1 || day <= 0 || day > len_months[isleap(year)][month]) {
        error(_("invalid day of month"));
        return;
    }
    dayoff = oadd(dayoff, eitol(day - 1));
    if (dayoff < min_time / SECSPERDAY) {
        error(_("time too small"));
        return;
    }
    if (dayoff > max_time / SECSPERDAY) {
        error(_("time too large"));
        return;
    }
    t = (zic_t)dayoff * SECSPERDAY;

    tod = gethms(fields[LP_TIME], _("invalid time of day"), FALSE);
    cp = fields[LP_CORR];
    {
        int positive;
        int count;

        if (strcmp(cp, "") == 0) { /* infile() turns "-" into "" */
            positive = FALSE;
            count = 1;
        } else if (strcmp(cp, "--") == 0) {
            positive = FALSE;
            count = 2;
        } else if (strcmp(cp, "+") == 0) {
            positive = TRUE;
            count = 1;
        } else if (strcmp(cp, "++") == 0) {
            positive = TRUE;
            count = 2;
        } else {
            error(_("illegal CORRECTION field on Leap line"));
            return;
        }
        if ((lp = byword(fields[LP_ROLL], leap_types)) == NULL) {
            error(_("illegal Rolling/Stationary field on Leap line"));
            return;
        }
        leapadd(tadd(t, tod), positive, lp->l_value, count);
    }
}

static void inlink(const char** fields, int nfields)
{
    struct link l;

    if (nfields != LINK_FIELDS) {
        error(_("wrong number of fields on Link line"));
        return;
    }
    if (*fields[LF_FROM] == '\0') {
        error(_("blank FROM field on Link line"));
        return;
    }
    if (*fields[LF_TO] == '\0') {
        error(_("blank TO field on Link line"));
        return;
    }
    l.l_filename = filename;
    l.l_linenum = linenum;
    l.l_from = ecpyalloc(fields[LF_FROM]);
    l.l_to = ecpyalloc(fields[LF_TO]);
    links = (struct link*)(void*)erealloc((char*)links, (int)((nlinks + 1) * sizeof *links));
    links[nlinks++] = l;
}

static void rulesub(struct rule* rp, const char* loyearp, const char* hiyearp, const char* typep, const char* monthp,
    const char* dayp, const char* timep)
{
    const struct lookup* lp = NULL;
    const char* cp = NULL;
    char* dp = NULL;
    char* ep = NULL;

    if ((lp = byword(monthp, mon_names)) == NULL) {
        error(_("invalid month name"));
        return;
    }
    rp->r_month = lp->l_value;
    rp->r_todisstd = FALSE;
    rp->r_todisgmt = FALSE;
    dp = ecpyalloc(timep);
    if (*dp != '\0') {
        ep = dp + strlen(dp) - 1;
        switch (lowerit(*ep)) {
            case 's': /* Standard */
                rp->r_todisstd = TRUE;
                rp->r_todisgmt = FALSE;
                *ep = '\0';
                break;
            case 'w': /* Wall */
                rp->r_todisstd = FALSE;
                rp->r_todisgmt = FALSE;
                *ep = '\0';
                break;
            case 'g': /* Greenwich */
            case 'u': /* Universal */
            case 'z': /* Zulu */
                rp->r_todisstd = TRUE;
                rp->r_todisgmt = TRUE;
                *ep = '\0';
                break;
            default:
                break;
        }
    }
    rp->r_tod = gethms(dp, _("invalid time of day"), FALSE);
    ifree(dp);
    dp = NULL;

    /*
     * Year work.
     */
    cp = loyearp;
    lp = byword(cp, begin_years);
    rp->r_lowasnum = lp == NULL;
    if (!rp->r_lowasnum) {
        switch ((int)lp->l_value) {
            case YR_MINIMUM:
                rp->r_loyear = INT_MIN;
                break;
            case YR_MAXIMUM:
                rp->r_loyear = INT_MAX;
                break;
            default: /* "cannot happen" */
                (void)fprintf(stderr, _("%s: panic: Invalid l_value %d\n"), progname, lp->l_value);
                exit(EXIT_FAILURE);
        }
    } else if (sscanf_s(cp, scheck(cp, "%d"), &rp->r_loyear) != 1) {
        error(_("invalid starting year"));
        return;
    }
    cp = hiyearp;
    lp = byword(cp, end_years);
    rp->r_hiwasnum = lp == NULL;
    if (!rp->r_hiwasnum) {
        switch ((int)lp->l_value) {
            case YR_MINIMUM:
                rp->r_hiyear = INT_MIN;
                break;
            case YR_MAXIMUM:
                rp->r_hiyear = INT_MAX;
                break;
            case YR_ONLY:
                rp->r_hiyear = rp->r_loyear;
                break;
            default: /* "cannot happen" */
                (void)fprintf(stderr, _("%s: panic: Invalid l_value %d\n"), progname, lp->l_value);
                exit(EXIT_FAILURE);
        }
    } else if (sscanf_s(cp, scheck(cp, "%d"), &rp->r_hiyear) != 1) {
        error(_("invalid ending year"));
        return;
    }
    if (rp->r_loyear > rp->r_hiyear) {
        error(_("starting year greater than ending year"));
        return;
    }
    if (*typep == '\0') {
        rp->r_yrtype = NULL;
    } else {
        if (rp->r_loyear == rp->r_hiyear) {
            error(_("typed single year"));
            return;
        }
        rp->r_yrtype = ecpyalloc(typep);
    }

    /*
     * Day work. Accept things such as:  1	last-Sunday  Sun<=20  Sun>=7
     */
    dp = ecpyalloc(dayp);
    if ((lp = byword(dp, lasts)) != NULL) {
        rp->r_dycode = DC_DOWLEQ;
        rp->r_wday = lp->l_value;
        rp->r_dayofmonth = len_months[1][rp->r_month];
    } else {
        if ((ep = strchr(dp, '<')) != NULL) {
            rp->r_dycode = DC_DOWLEQ;
        } else if ((ep = strchr(dp, '>')) != NULL) {
            rp->r_dycode = DC_DOWGEQ;
        } else {
            ep = dp;
            rp->r_dycode = DC_DOM;
        }
        if (rp->r_dycode != DC_DOM) {
            *ep++ = 0;
            if (*ep++ != '=') {
                error(_("invalid day of month"));
                ifree(dp);
                dp = NULL;
                return;
            }
            if ((lp = byword(dp, wday_names)) == NULL) {
                error(_("invalid weekday name"));
                ifree(dp);
                dp = NULL;
                return;
            }
            rp->r_wday = lp->l_value;
        }
        if (sscanf_s(ep, scheck(ep, "%d"), &rp->r_dayofmonth) != 1 || rp->r_dayofmonth <= 0 ||
            (rp->r_dayofmonth > len_months[1][rp->r_month])) {
            error(_("invalid day of month"));
            ifree(dp);
            dp = NULL;
            return;
        }
    }
    ifree(dp);
    dp = NULL;
}

static void convert(long val, char* buf)
{
    int i;
    int shift;

    for (i = 0, shift = 24; i < 4; ++i, shift -= 8) {
        buf[i] = val >> shift;
    }
}

static void convert64(zic_t val, char* buf)
{
    int i;
    int shift;

    for (i = 0, shift = 56; i < 8; ++i, shift -= 8) {
        buf[i] = val >> shift;
    }
}

static void puttzcode(long val, FILE* fp)
{
    char buf[4];

    convert(val, buf);
    (void)fwrite((void*)buf, (size_t)sizeof buf, (size_t)1, fp);
}

static void puttzcode64(zic_t val, FILE* fp)
{
    char buf[8];

    convert64(val, buf);
    (void)fwrite((void*)buf, (size_t)sizeof buf, (size_t)1, fp);
}

static int atcomp(const void* avp, const void* bvp)
{
    const zic_t a = ((const struct attype*)avp)->at;
    const zic_t b = ((const struct attype*)bvp)->at;

    return (a < b) ? -1 : (a > b);
}

static int is32(zic_t x)
{
    return x == ((zic_t)((int32)x));
}

static void writezone(const char* name, const char* string)
{
    FILE* fp = NULL;
    int i, j;
    int leapcnt32, leapi32;
    int timecnt32, timei32;
    int pass;
    static char* fullname = NULL;
    static const struct tzhead tzh0 = {{0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}, {0}};
    static struct tzhead tzh;
    zic_t ats[TZ_MAX_TIMES];
    unsigned char types[TZ_MAX_TIMES];
    int rc = 0;

    /*
     * Sort.
     */
    if (timecnt > 1) {
        (void)qsort((void*)attypes, (size_t)(unsigned int)timecnt, (size_t)sizeof *attypes, atcomp);
    }

    /*
     * Optimize.
     */
    {
        int fromi;
        int toi;

        toi = 0;
        fromi = 0;
        while (fromi < timecnt && attypes[fromi].at < min_time) {
            ++fromi;
        }
        if (isdsts[0] == 0) {
            while (fromi < timecnt && attypes[fromi].type == 0) {
                ++fromi; /* handled by default rule */
            }
        }
        for (; fromi < timecnt; ++fromi) {
            if (toi != 0 && ((attypes[fromi].at + gmtoffs[attypes[toi - 1].type]) <=
                                (attypes[toi - 1].at + gmtoffs[toi == 1 ? 0 : attypes[toi - 2].type]))) {
                attypes[toi - 1].type = attypes[fromi].type;
                continue;
            }
            if (toi == 0 || attypes[toi - 1].type != attypes[fromi].type) {
                attypes[toi++] = attypes[fromi];
            }
        }
        timecnt = toi;
    }

    /*
     * Transfer.
     */
    for (i = 0; i < timecnt; ++i) {
        ats[i] = attypes[i].at;
        types[i] = attypes[i].type;
    }

    /*
     * Correct for leap seconds.
     */
    for (i = 0; i < timecnt; ++i) {
        j = leapcnt;
        while (--j >= 0) {
            if (ats[i] > trans[j] - corr[j]) {
                ats[i] = tadd(ats[i], corr[j]);
                break;
            }
        }
    }

    /*
     * Figure out 32-bit-limited starts and counts.
     */
    timecnt32 = timecnt;
    timei32 = 0;
    leapcnt32 = leapcnt;
    leapi32 = 0;
    while (timecnt32 > 0 && !is32(ats[timecnt32 - 1])) {
        --timecnt32;
    }
    while (timecnt32 > 0 && !is32(ats[timei32])) {
        --timecnt32;
        ++timei32;
    }
    while (leapcnt32 > 0 && !is32(trans[leapcnt32 - 1])) {
        --leapcnt32;
    }
    while (leapcnt32 > 0 && !is32(trans[leapi32])) {
        --leapcnt32;
        ++leapi32;
    }
    fullname = erealloc(fullname, (int)(strlen(directory) + 1 + strlen(name) + 1));
    rc = sprintf_s(fullname, (strlen(directory) + 1 + strlen(name) + 1), "%s/%s", directory, name);
    securec_check_ss_c(rc, "", "");

    /*
     * Remove old file, if any, to snap links.
     */
    if (!itsdir(fullname) && remove(fullname) != 0 && errno != ENOENT) {
        const char* e = gs_strerror(errno);

        (void)fprintf(stderr, _("%s: Cannot remove %s: %s\n"), progname, fullname, e);
        exit(EXIT_FAILURE);
    }
    if ((fp = fopen(fullname, "wb")) == NULL) {
        if (mkdirs(fullname) != 0) {
            (void)exit(EXIT_FAILURE);
        }
        if ((fp = fopen(fullname, "wb")) == NULL) {
            const char* e = gs_strerror(errno);

            (void)fprintf(stderr, _("%s: Cannot create %s: %s\n"), progname, fullname, e);
            exit(EXIT_FAILURE);
        }
    }
    for (pass = 1; pass <= 2; ++pass) {
        register int thistimei, thistimecnt;
        register int thisleapi, thisleapcnt;
        register int thistimelim, thisleaplim;
        int writetype[TZ_MAX_TIMES];
        int typemap[TZ_MAX_TYPES];
        register int thistypecnt;
        char thischars[TZ_MAX_CHARS];
        char thischarcnt;
        int indmap[TZ_MAX_CHARS];

        if (pass == 1) {
            thistimei = timei32;
            thistimecnt = timecnt32;
            thisleapi = leapi32;
            thisleapcnt = leapcnt32;
        } else {
            thistimei = 0;
            thistimecnt = timecnt;
            thisleapi = 0;
            thisleapcnt = leapcnt;
        }
        thistimelim = thistimei + thistimecnt;
        thisleaplim = thisleapi + thisleapcnt;
        for (i = 0; i < typecnt; ++i) {
            writetype[i] = thistimecnt == timecnt;
        }
        if (thistimecnt == 0) {
            /*
             * * No transition times fall in the current * (32- or 64-bit)
             * window.
             */
            if (typecnt != 0) {
                writetype[typecnt - 1] = TRUE;
            }
        } else {
            for (i = thistimei - 1; i < thistimelim; ++i) {
                if (i >= 0) {
                    writetype[types[i]] = TRUE;
                }
            }

            /*
             * * For America/Godthab and Antarctica/Palmer
             */
            if (thistimei == 0) {
                writetype[0] = TRUE;
            }
        }
        thistypecnt = 0;
        for (i = 0; i < typecnt; ++i) {
            typemap[i] = writetype[i] ? thistypecnt++ : -1;
        }
        for (i = 0; (size_t)(unsigned int)i < sizeof(indmap) / sizeof(indmap[0]); ++i) {
            indmap[i] = -1;
        }
        thischarcnt = 0;
        for (i = 0; i < typecnt; ++i) {
            register char* thisabbr = NULL;

            if (!writetype[i]) {
                continue;
            }
            if (indmap[abbrinds[i]] >= 0) {
                continue;
            }
            thisabbr = &chars[abbrinds[i]];
            for (j = 0; j < thischarcnt; ++j) {
                if (strcmp(&thischars[j], thisabbr) == 0) {
                    break;
                }
            }
            if (j == thischarcnt) {
                int ret = strcpy_s(&thischars[(int)thischarcnt], TZ_MAX_CHARS - (int)thischarcnt, thisabbr);
                securec_check_c(ret, "\0", "\0");
                thischarcnt += strlen(thisabbr) + 1;
            }
            indmap[abbrinds[i]] = j;
        }
#define DO(field) (void)fwrite((void*)tzh.field, (size_t)sizeof tzh.field, (size_t)1, fp)
        tzh = tzh0;
        int rc = strncpy_s(tzh.tzh_magic, sizeof(tzh.tzh_magic), TZ_MAGIC, sizeof tzh.tzh_magic);
        securec_check_c(rc, "", "");
        tzh.tzh_version[0] = ZIC_VERSION;
        convert(eitol(thistypecnt), tzh.tzh_ttisgmtcnt);
        convert(eitol(thistypecnt), tzh.tzh_ttisstdcnt);
        convert(eitol(thisleapcnt), tzh.tzh_leapcnt);
        convert(eitol(thistimecnt), tzh.tzh_timecnt);
        convert(eitol(thistypecnt), tzh.tzh_typecnt);
        convert(eitol(thischarcnt), tzh.tzh_charcnt);
        DO(tzh_magic);
        DO(tzh_version);
        DO(tzh_reserved);
        DO(tzh_ttisgmtcnt);
        DO(tzh_ttisstdcnt);
        DO(tzh_leapcnt);
        DO(tzh_timecnt);
        DO(tzh_typecnt);
        DO(tzh_charcnt);
#undef DO
        for (i = thistimei; i < thistimelim; ++i) {
            if (pass == 1) {
                puttzcode((long)ats[i], fp);
            } else {
                puttzcode64(ats[i], fp);
            }
        }
        for (i = thistimei; i < thistimelim; ++i) {
            unsigned char uc;

            uc = typemap[types[i]];
            (void)fwrite((void*)&uc, (size_t)sizeof uc, (size_t)1, fp);
        }
        for (i = 0; i < typecnt; ++i) {
            if (writetype[i]) {
                puttzcode(gmtoffs[i], fp);
                (void)putc(isdsts[i], fp);
                (void)putc((unsigned char)indmap[abbrinds[i]], fp);
            }
        }
        if (thischarcnt != 0) {
            (void)fwrite((void*)thischars, (size_t)sizeof(thischars[0]), (size_t)(unsigned int)thischarcnt, fp);
        }
        for (i = thisleapi; i < thisleaplim; ++i) {
            register zic_t todo;

            if (roll[i]) {
                if (timecnt == 0 || trans[i] < ats[0]) {
                    j = 0;
                    while (isdsts[j]) {
                        if (++j >= typecnt) {
                            j = 0;
                            break;
                        }
                    }
                } else {
                    j = 1;
                    while (j < timecnt && trans[i] >= ats[j]) {
                        ++j;
                    }
                    j = types[j - 1];
                }
                todo = tadd(trans[i], -gmtoffs[j]);
            } else {
                todo = trans[i];
            }
            if (pass == 1) {
                puttzcode((long)todo, fp);
            } else {
                puttzcode64(todo, fp);
            }
            puttzcode(corr[i], fp);
        }
        for (i = 0; i < typecnt; ++i) {
            if (writetype[i]) {
                (void)putc(ttisstds[i], fp);
            }
        }
        for (i = 0; i < typecnt; ++i) {
            if (writetype[i]) {
                (void)putc(ttisgmts[i], fp);
            }
        }
    }
    (void)fprintf(fp, "\n%s\n", string);
    if (ferror(fp) || fclose(fp)) {
        (void)fprintf(stderr, _("%s: Error writing %s\n"), progname, fullname);
        exit(EXIT_FAILURE);
    }
}

static bool checkIndex(int idx, int bound, bool exit_on_failure = true)
{
    if ((idx >= 0) && (idx < bound)) {
        return true;
    }

    /* opps, out of bounds, should exit or return false */
    if (exit_on_failure) {
        (void)fprintf(stderr, _("%s:ERROR index %d out of array bounds %d\n"), progname, idx, bound);
        exit(EXIT_FAILURE);
    }

    return false;
}

static void doabbr(char* abbr, int abbr_size, const char* format, const char* letters, int isdst, int doquotes)
{
    char* cp = NULL;
    char* slashp = NULL;
    int len;
    errno_t rc;

    slashp = (char*)strchr(format, '/');
    if (slashp == NULL) {
        if (letters == NULL) {
            rc = strcpy_s(abbr, strlen(format) + 1, format);
            securec_check_c(rc, "\0", "\0");
        } else {
            rc = sprintf_s(abbr, strlen(format) + strlen(letters) + 2, format, letters);
            securec_check_ss_c(rc, "", "");
        }
    } else if (isdst) {
            rc = strcpy_s(abbr, strlen(slashp + 1) + 1, slashp + 1);
            securec_check_c(rc, "\0", "\0");
        } else {
        if (slashp > format) {
            rc = strncpy_s(abbr, strlen(format) + sizeof(unsigned long int) + 1, format, (unsigned)(slashp - format));
            securec_check_c(rc, "\0", "\0");
        }
        if (checkIndex(slashp - format, abbr_size)) {
            abbr[slashp - format] = '\0';
        }
    }
    if (!doquotes) {
        return;
    }
    for (cp = abbr; *cp != '\0'; ++cp) {
        if (strchr("ABCDEFGHIJKLMNOPQRSTUVWXYZ", *cp) == NULL && strchr("abcdefghijklmnopqrstuvwxyz", *cp) == NULL) {
            break;
        }
    }
    len = strlen(abbr);
    if (len > 0 && *cp == '\0') {
        return;
    }

    if (checkIndex(len + 2, abbr_size)) {
        abbr[len + 2] = '\0';
    }

    if (checkIndex(len + 1, abbr_size)) {
        abbr[len + 1] = '>';
    }

    checkIndex(len, abbr_size);

    for (; len > 0; --len) {
        abbr[len] = abbr[len - 1];
    }
    abbr[0] = '<';
}

static void updateminmax(int x)
{
    if (min_year > x) {
        min_year = x;
    }
    if (max_year < x) {
        max_year = x;
    }
}

static int stringoffset(char* result, long offset)
{
    int hours;
    int minutes;
    int seconds;

    result[0] = '\0';
    if (offset < 0) {
        (void)strcpy(result, "-");
        offset = -offset;
    }
    seconds = offset % SECSPERMIN;
    offset /= SECSPERMIN;
    minutes = offset % MINSPERHOUR;
    offset /= MINSPERHOUR;
    hours = offset;
    if (hours >= HOURSPERDAY) {
        result[0] = '\0';
        return -1;
    }
    (void)sprintf(end(result), "%d", hours);
    if (minutes != 0 || seconds != 0) {
        (void)sprintf(end(result), ":%02d", minutes);
        if (seconds != 0)
            (void)sprintf(end(result), ":%02d", seconds);
    }
    return 0;
}

static int stringrule(char* result, const struct rule* rp, long dstoff, long gmtoff)
{
    long tod;

    result = end(result);
    if (rp->r_dycode == DC_DOM) {
        int month, total;

        if (rp->r_dayofmonth == 29 && rp->r_month == TM_FEBRUARY)
            return -1;
        total = 0;
        for (month = 0; month < rp->r_month; ++month) {
            total += len_months[0][month];
        }
        (void)sprintf(result, "J%d", total + rp->r_dayofmonth);
    } else {
        int week;

        if (rp->r_dycode == DC_DOWGEQ) {
            week = 1 + rp->r_dayofmonth / DAYSPERWEEK;
            if ((week - 1) * DAYSPERWEEK + 1 != rp->r_dayofmonth) {
                return -1;
            }
        } else if (rp->r_dycode == DC_DOWLEQ) {
            if (rp->r_dayofmonth == len_months[1][rp->r_month]) {
                week = 5;
            } else {
                week = 1 + rp->r_dayofmonth / DAYSPERWEEK;
                if (week * DAYSPERWEEK - 1 != rp->r_dayofmonth) {
                    return -1;
                }
            }
        } else {
            return -1; /* "cannot happen" */
        }
        (void)sprintf(result, "M%d.%d.%d", rp->r_month + 1, week, rp->r_wday);
    }
    tod = rp->r_tod;
    if (rp->r_todisgmt) {
        tod += gmtoff;
    }
    if (rp->r_todisstd && rp->r_stdoff == 0) {
        tod += dstoff;
    }
    if (tod < 0) {
        result[0] = '\0';
        return -1;
    }
    if (tod != 2 * SECSPERMIN * MINSPERHOUR) {
        (void)strcat(result, "/");
        if (stringoffset(end(result), tod) != 0)
            return -1;
    }
    return 0;
}

static void stringzone(char* result, int result_size, const struct zone* zpfirst, int zonecount)
{
    const struct zone* zp = NULL;
    struct rule* rp = NULL;
    struct rule* stdrp = NULL;
    struct rule* dstrp = NULL;
    int i;
    const char* abbrvar = NULL;

    result[0] = '\0';
    zp = zpfirst + zonecount - 1;
    stdrp = dstrp = NULL;
    for (i = 0; i < zp->z_nrules; ++i) {
        rp = &zp->z_rules[i];
        if (rp->r_hiwasnum || rp->r_hiyear != INT_MAX) {
            continue;
        }
        if (rp->r_yrtype != NULL) {
            continue;
        }
        if (rp->r_stdoff == 0) {
            if (stdrp == NULL) {
                stdrp = rp;
            } else {
                return;
            }
        } else {
            if (dstrp == NULL) {
                dstrp = rp;
            } else {
                return;
            }
        }
    }
    if (stdrp == NULL && dstrp == NULL) {
        /*
         * There are no rules running through "max". Let's find the latest
         * rule.
         */
        for (i = 0; i < zp->z_nrules; ++i) {
            rp = &zp->z_rules[i];
            if (stdrp == NULL || rp->r_hiyear > stdrp->r_hiyear ||
                (rp->r_hiyear == stdrp->r_hiyear && rp->r_month > stdrp->r_month))
                stdrp = rp;
        }
        if (stdrp != NULL && stdrp->r_stdoff != 0) {
            return; /* We end up in DST (a POSIX no-no). */
        }

        /*
         * Horrid special case: if year is 2037, presume this is a zone
         * handled on a year-by-year basis; do not try to apply a rule to the
         * zone.
         */
        if (stdrp != NULL && stdrp->r_hiyear == 2037) {
            return;
        }
    }
    if (stdrp == NULL && (zp->z_nrules != 0 || zp->z_stdoff != 0)) {
        return;
    }
    abbrvar = (stdrp == NULL) ? "" : stdrp->r_abbrvar;
    doabbr(result, result_size, zp->z_format, abbrvar, FALSE, TRUE);
    if (stringoffset(end(result), -zp->z_gmtoff) != 0) {
        result[0] = '\0';
        return;
    }
    if (dstrp == NULL) {
        return;
    }

    /*
     *  About size compute:
     *
     *  H e l l o \0
     *  0 1 2 3 4 5 6 7 8 9
     *  ^result=0
     *          ^end=5
     *  total size = 10
     *  size left = size - (end - result) = 10 - (5 -0) = 5
     */

    doabbr(end(result), result_size - (end(result) - result), zp->z_format, dstrp->r_abbrvar, TRUE, TRUE);
    if (dstrp->r_stdoff != SECSPERMIN * MINSPERHOUR)
        if (stringoffset(end(result), -(zp->z_gmtoff + dstrp->r_stdoff)) != 0) {
            result[0] = '\0';
            return;
        }
    (void)strcat(result, ",");
    if (stringrule(result, dstrp, dstrp->r_stdoff, zp->z_gmtoff) != 0) {
        result[0] = '\0';
        return;
    }
    (void)strcat(result, ",");
    if (stdrp == NULL) {
        result[0] = '\0';
        return;
    }
    if (stringrule(result, stdrp, dstrp->r_stdoff, zp->z_gmtoff) != 0) {
        result[0] = '\0';
        return;
    }
}

static void outzone(const struct zone* zpfirst, int zonecount)
{
    const struct zone* zp = NULL;
    struct rule* rp = NULL;
    int i, j;
    int usestart, useuntil;
    zic_t starttime = 0;
    zic_t untiltime = 0;
    long gmtoff;
    long stdoff;
    int year;
    long startoff;
    int startttisstd;
    int startttisgmt;
    int type;
    char* startbuf = NULL;
    char* ab = NULL;
    char* envvar = NULL;
    int rc  = 0;

    const int max_abbr_len = 2 + max_format_len + max_abbrvar_len;
    const int max_envvar_len = 2 * max_abbr_len + 5 * 9;
    const int startbuf_size = max_abbr_len + 1;
    const int envvar_size = max_envvar_len + 1;
    startbuf = emalloc(startbuf_size);
    ab = emalloc(startbuf_size);
    envvar = emalloc(envvar_size);

    /*
     * Now. . .finally. . .generate some useful data!
     */
    timecnt = 0;
    typecnt = 0;
    charcnt = 0;

    /*
     * Thanks to Earl Chew for noting the need to unconditionally initialize
     * startttisstd.
     */
    startttisstd = FALSE;
    startttisgmt = FALSE;
    min_year = max_year = EPOCH_YEAR;
    if (leapseen) {
        updateminmax(leapminyear);
        updateminmax(leapmaxyear + (int)(leapmaxyear < INT_MAX));
    }
    for (i = 0; i < zonecount; ++i) {
        zp = &zpfirst[i];
        if (i < zonecount - 1) {
            updateminmax(zp->z_untilrule.r_loyear);
        }
        for (j = 0; j < zp->z_nrules; ++j) {
            rp = &zp->z_rules[j];
            if (rp->r_lowasnum) {
                updateminmax(rp->r_loyear);
            }
            if (rp->r_hiwasnum) {
                updateminmax(rp->r_hiyear);
            }
        }
    }

    /*
     * Generate lots of data if a rule can't cover all future times.
     */
    stringzone(envvar, envvar_size, zpfirst, zonecount);
    if (noise && envvar[0] == '\0') {
        char* wp = NULL;

        wp = ecpyalloc(_("no POSIX environment variable for zone"));
        wp = ecatalloc(wp, " ");
        wp = ecatalloc(wp, zpfirst->z_name);
        warning(wp);
        ifree(wp);
        wp = NULL;
    }
    if (envvar[0] == '\0') {
        if (min_year >= INT_MIN + YEARSPERREPEAT) {
            min_year -= YEARSPERREPEAT;
        } else {
            min_year = INT_MIN;
        }
        if (max_year <= INT_MAX - YEARSPERREPEAT) {
            max_year += YEARSPERREPEAT;
        } else {
            max_year = INT_MAX;
        }
    }

    /*
     * For the benefit of older systems, generate data from 1900 through 2037.
     */
    if (min_year > 1900) {
        min_year = 1900;
    }
    if (max_year < 2037) {
        max_year = 2037;
    }
    for (i = 0; i < zonecount; ++i) {
        /*
         * A guess that may well be corrected later.
         */
        stdoff = 0;
        zp = &zpfirst[i];
        usestart = i > 0 && (zp - 1)->z_untiltime > min_time;
        useuntil = i < (zonecount - 1);
        if (useuntil && zp->z_untiltime <= min_time) {
            continue;
        }
        gmtoff = zp->z_gmtoff;
        eat(zp->z_filename, zp->z_linenum);
        *startbuf = '\0';
        startoff = zp->z_gmtoff;
        if (zp->z_nrules == 0) {
            stdoff = zp->z_stdoff;
            doabbr(startbuf, startbuf_size, zp->z_format, (char*)NULL, stdoff != 0, FALSE);
            type = addtype(oadd(zp->z_gmtoff, stdoff), startbuf, stdoff != 0, startttisstd, startttisgmt);
            if (usestart) {
                addtt(starttime, type);
                usestart = FALSE;
            } else if (stdoff != 0) {
                addtt(min_time, type);
            }
        } else {
            for (year = min_year; year <= max_year; ++year) {
                if (useuntil && year > zp->z_untilrule.r_hiyear) {
                    break;
                }

                /*
                 * Mark which rules to do in the current year. For those to
                 * do, calculate rpytime(rp, year);
                 */
                for (j = 0; j < zp->z_nrules; ++j) {
                    rp = &zp->z_rules[j];
                    eats(zp->z_filename, zp->z_linenum, rp->r_filename, rp->r_linenum);
                    rp->r_todo = year >= rp->r_loyear && year <= rp->r_hiyear && yearistype(year, rp->r_yrtype);
                    if (rp->r_todo) {
                        rp->r_temp = rpytime(rp, year);
                    }
                }
                for (;;) {
                    int k;
                    zic_t jtime;
                    zic_t ktime = 0;
                    long offset;

                    if (useuntil) {
                        /*
                         * Turn untiltime into UTC assuming the current gmtoff
                         * and stdoff values.
                         */
                        untiltime = zp->z_untiltime;
                        if (!zp->z_untilrule.r_todisgmt) {
                            untiltime = tadd(untiltime, -gmtoff);
                        }
                        if (!zp->z_untilrule.r_todisstd) {
                            untiltime = tadd(untiltime, -stdoff);
                        }
                    }

                    /*
                     * Find the rule (of those to do, if any) that takes
                     * effect earliest in the year.
                     */
                    k = -1;
                    for (j = 0; j < zp->z_nrules; ++j) {
                        rp = &zp->z_rules[j];
                        if (!rp->r_todo) {
                            continue;
                        }
                        eats(zp->z_filename, zp->z_linenum, rp->r_filename, rp->r_linenum);
                        offset = rp->r_todisgmt ? 0 : gmtoff;
                        if (!rp->r_todisstd) {
                            offset = oadd(offset, stdoff);
                        }
                        jtime = rp->r_temp;
                        if (jtime == min_time || jtime == max_time) {
                            continue;
                        }
                        jtime = tadd(jtime, -offset);
                        if (k < 0 || jtime < ktime) {
                            k = j;
                            ktime = jtime;
                        }
                    }
                    if (k < 0) {
                        break; /* go on to next year */
                    }
                    rp = &zp->z_rules[k];
                    rp->r_todo = FALSE;
                    if (useuntil && ktime >= untiltime) {
                        break;
                    }
                    stdoff = rp->r_stdoff;
                    if (usestart && ktime == starttime) {
                        usestart = FALSE;
                    }
                    if (usestart) {
                        if (ktime < starttime) {
                            startoff = oadd(zp->z_gmtoff, stdoff);
                            doabbr(startbuf, startbuf_size, zp->z_format, rp->r_abbrvar, rp->r_stdoff != 0, FALSE);
                            continue;
                        }
                        if (*startbuf == '\0' && startoff == oadd(zp->z_gmtoff, stdoff)) {
                            doabbr(startbuf, startbuf_size, zp->z_format, rp->r_abbrvar, rp->r_stdoff != 0, FALSE);
                        }
                    }
                    eats(zp->z_filename, zp->z_linenum, rp->r_filename, rp->r_linenum);
                    doabbr(ab, startbuf_size, zp->z_format, rp->r_abbrvar, rp->r_stdoff != 0, FALSE);
                    offset = oadd(zp->z_gmtoff, rp->r_stdoff);
                    type = addtype(offset, ab, rp->r_stdoff != 0, rp->r_todisstd, rp->r_todisgmt);
                    addtt(ktime, type);
                }
            }
        }
        if (usestart) {
            if (*startbuf == '\0' && zp->z_format != NULL && strchr(zp->z_format, '%') == NULL &&
                strchr(zp->z_format, '/') == NULL) {
                    rc = strcpy_s(startbuf, startbuf_size, zp->z_format);
                    securec_check_c(rc, "", "");
                }
            eat(zp->z_filename, zp->z_linenum);
            if (*startbuf == '\0') {
                error(_("cannot determine time zone abbreviation to use just after until time"));
            } else {
                addtt(starttime, addtype(startoff, startbuf, startoff != zp->z_gmtoff, startttisstd, startttisgmt));
            }
        }

        /*
         * Now we may get to set starttime for the next zone line.
         */
        if (useuntil) {
            startttisstd = zp->z_untilrule.r_todisstd;
            startttisgmt = zp->z_untilrule.r_todisgmt;
            starttime = zp->z_untiltime;
            if (!startttisstd) {
                starttime = tadd(starttime, -stdoff);
            }
            if (!startttisgmt) {
                starttime = tadd(starttime, -gmtoff);
            }
        }
    }
    writezone(zpfirst->z_name, envvar);
    ifree(startbuf);
    ifree(ab);
    ifree(envvar);
    startbuf = NULL;
    ab = NULL;
    envvar = NULL;
}

static void addtt(const zic_t starttime, int type)
{
    if (starttime <= min_time || (timecnt == 1 && attypes[0].at < min_time)) {
        gmtoffs[0] = gmtoffs[type];
        isdsts[0] = isdsts[type];
        ttisstds[0] = ttisstds[type];
        ttisgmts[0] = ttisgmts[type];
        if (abbrinds[type] != 0)
            (void)strcpy(chars, &chars[abbrinds[type]]);
        abbrinds[0] = 0;
        charcnt = strlen(chars) + 1;
        typecnt = 1;
        timecnt = 0;
        type = 0;
    }
    if (timecnt >= TZ_MAX_TIMES) {
        error(_("too many transitions?!"));
        exit(EXIT_FAILURE);
    }
    attypes[timecnt].at = starttime;
    attypes[timecnt].type = type;
    ++timecnt;
}

static int addtype(long gmtoff, const char* abbr, int isdst, int ttisstd, int ttisgmt)
{
    int i;
    int j;

    if (isdst != TRUE && isdst != FALSE) {
        error(_("internal error - addtype called with bad isdst"));
        exit(EXIT_FAILURE);
    }
    if (ttisstd != TRUE && ttisstd != FALSE) {
        error(_("internal error - addtype called with bad ttisstd"));
        exit(EXIT_FAILURE);
    }
    if (ttisgmt != TRUE && ttisgmt != FALSE) {
        error(_("internal error - addtype called with bad ttisgmt"));
        exit(EXIT_FAILURE);
    }

    /*
     * See if there's already an entry for this zone type. If so, just return
     * its index.
     */
    for (i = 0; i < typecnt; ++i) {
        if (gmtoff == gmtoffs[i] && isdst == isdsts[i] && strcmp(abbr, &chars[abbrinds[i]]) == 0 &&
            ttisstd == ttisstds[i] && ttisgmt == ttisgmts[i]) {
            return i;
        }
    }

    /*
     * There isn't one; add a new one, unless there are already too many.
     */
    if (typecnt >= TZ_MAX_TYPES) {
        error(_("too many local time types"));
        exit(EXIT_FAILURE);
    }

    if (!(-UTC_OFFSET_MAX_NUM - 1L <= gmtoff && gmtoff <= UTC_OFFSET_MAX_NUM)) {
        error(_("UTC offset out of range"));
        exit(EXIT_FAILURE);
    }
    gmtoffs[i] = gmtoff;
    isdsts[i] = isdst;
    ttisstds[i] = ttisstd;
    ttisgmts[i] = ttisgmt;

    for (j = 0; j < charcnt; ++j) {
        if (strcmp(&chars[j], abbr) == 0) {
            break;
        }
    }
    if (j == charcnt) {
        newabbr(abbr);
    }
    abbrinds[i] = j;
    ++typecnt;
    return i;
}

static void leapadd(const zic_t t, int positive, int rolling, int count)
{
    int i;
    int j;

    if (leapcnt + (positive ? count : 1) > TZ_MAX_LEAPS) {
        error(_("too many leap seconds"));
        exit(EXIT_FAILURE);
    }
    for (i = 0; i < leapcnt; ++i) {
        if (t <= trans[i]) {
            if (t == trans[i]) {
                error(_("repeated leap second moment"));
                exit(EXIT_FAILURE);
            }
            break;
        }
    }
    do {
        for (j = leapcnt; j > i; --j) {
            trans[j] = trans[j - 1];
            corr[j] = corr[j - 1];
            roll[j] = roll[j - 1];
        }
        trans[i] = t;
        corr[i] = positive ? 1L : eitol(-count);
        roll[i] = rolling;
        ++leapcnt;
    } while (positive && --count != 0);
}

static void adjleap(void)
{
    int i;
    long last = 0;

    /*
     * propagate leap seconds forward
     */
    for (i = 0; i < leapcnt; ++i) {
        trans[i] = tadd(trans[i], last);
        last = corr[i] += last;
    }
}

static int yearistype(int year, const char* type)
{
    static THR_LOCAL char* buf;
    int result;

    if (type == NULL || *type == '\0')
        return TRUE;
    buf = erealloc(buf, (int)(132 + strlen(yitcommand) + strlen(type)));
    (void)sprintf(buf, "%s %d %s", yitcommand, year, type);
    result = gs_system_security(buf);
    if (WIFEXITED(result)) {
        switch (WEXITSTATUS(result)) {
            case 0:
                return TRUE;
            case 1:
                return FALSE;
            default:
                break;
        }
    }
    error(_("Wild result from command execution"));
    (void)fprintf(stderr, _("%s: command was '%s', result was %d\n"), progname, buf, result);
    for (;;) {
        exit(EXIT_FAILURE);
    }
}

static int lowerit(int a)
{
    a = (unsigned char)a;
    return (isascii(a) && isupper(a)) ? tolower(a) : a;
}

static int ciequal(const char* ap, const char* bp)
{
    while (lowerit(*ap) == lowerit(*bp++)) {
        if (*ap++ == '\0') {
            return TRUE;
        }
    }
    return FALSE;
}

static int itsabbr(const char* abbr, const char* word)
{
    if (lowerit(*abbr) != lowerit(*word)) {
        return FALSE;
    }
    ++word;
    while (*++abbr != '\0') {
        do {
            if (*word == '\0') {
                return FALSE;
            }
        } while (lowerit(*word++) != lowerit(*abbr));
    }
    return TRUE;
}

static const struct lookup* byword(const char* word, const struct lookup* table)
{
    const struct lookup* foundlp = NULL;
    const struct lookup* lp = NULL;

    if (word == NULL || table == NULL) {
        return NULL;
    }

    /*
     * Look for exact match.
     */
    for (lp = table; lp->l_word != NULL; ++lp) {
        if (ciequal(word, lp->l_word)) {
            return lp;
        }
    }

    /*
     * Look for inexact match.
     */
    foundlp = NULL;
    for (lp = table; lp->l_word != NULL; ++lp) {
        if (itsabbr(word, lp->l_word)) {
            if (foundlp == NULL) {
                foundlp = lp;
            } else {
                return NULL; /* multiple inexact matches */
            }
        }
    }
    return foundlp;
}

static char** getfields(char* cp)
{
    char* dp = NULL;
    char** array;
    int nsubs;

    if (cp == NULL) {
        return NULL;
    }
    array = (char**)(void*)emalloc((int)((strlen(cp) + 1) * sizeof *array));
    nsubs = 0;
    for (;;) {
        while (isascii((unsigned char)*cp) && isspace((unsigned char)*cp)) {
            ++cp;
        }
        if (*cp == '\0' || *cp == '#') {
            break;
        }
        array[nsubs++] = dp = cp;
        do {
            if ((*dp = *cp++) != '"') {
                ++dp;
            } else {
                while ((*dp = *cp++) != '"') {
                    if (*dp != '\0') {
                        ++dp;
                    } else {
                        error(_("Odd number of quotation marks"));
                        exit(1);
                    }
                }
            }
        } while (*cp != '\0' && *cp != '#' && (!isascii(*cp) || !isspace((unsigned char)*cp)));
        if (isascii(*cp) && isspace((unsigned char)*cp)) {
            ++cp;
        }
        *dp = '\0';
    }
    array[nsubs] = NULL;
    return array;
}

static long oadd(long t1, long t2)
{
    long t;

    t = t1 + t2;
    if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
        error(_("time overflow"));
        exit(EXIT_FAILURE);
    }
    return t;
}

static zic_t tadd(const zic_t t1, long t2)
{
    zic_t t;

    if (t1 == max_time && t2 > 0) {
        return max_time;
    }
    if (t1 == min_time && t2 < 0) {
        return min_time;
    }
    t = t1 + t2;
    if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
        error(_("time overflow"));
        exit(EXIT_FAILURE);
    }
    return t;
}

/*
 * Given a rule, and a year, compute the date - in seconds since January 1,
 * 1970, 00:00 LOCAL time - in that year that the rule refers to.
 */
static zic_t rpytime(const struct rule* rp, int wantedy)
{
    int y, m, i;
    long dayoff; /* with a nod to Margaret O. */
    zic_t t;

    if (wantedy == INT_MIN) {
        return min_time;
    }
    if (wantedy == INT_MAX) {
        return max_time;
    }
    dayoff = 0;
    m = TM_JANUARY;
    y = EPOCH_YEAR;
    while (wantedy != y) {
        if (wantedy > y) {
            i = len_years[isleap(y)];
            ++y;
        } else {
            --y;
            i = -len_years[isleap(y)];
        }
        dayoff = oadd(dayoff, eitol(i));
    }
    while (m != rp->r_month) {
        i = len_months[isleap(y)][m];
        dayoff = oadd(dayoff, eitol(i));
        ++m;
    }
    i = rp->r_dayofmonth;
    if (m == TM_FEBRUARY && i == 29 && !isleap(y)) {
        if (rp->r_dycode == DC_DOWLEQ) {
            --i;
        } else {
            error(_("use of 2/29 in non leap-year"));
            exit(EXIT_FAILURE);
        }
    }
    --i;
    dayoff = oadd(dayoff, eitol(i));
    if (rp->r_dycode == DC_DOWGEQ || rp->r_dycode == DC_DOWLEQ) {
        long wday;

#define LDAYSPERWEEK ((long)DAYSPERWEEK)
        wday = eitol(EPOCH_WDAY);

        /*
         * Don't trust mod of negative numbers.
         */
        if (dayoff >= 0) {
            wday = (wday + dayoff) % LDAYSPERWEEK;
        } else {
            wday -= ((-dayoff) % LDAYSPERWEEK);
            if (wday < 0) {
                wday += LDAYSPERWEEK;
            }
        }
        while (wday != eitol(rp->r_wday)) {
            if (rp->r_dycode == DC_DOWGEQ) {
                dayoff = oadd(dayoff, (long)1);
                if (++wday >= LDAYSPERWEEK) {
                    wday = 0;
                }
                ++i;
            } else {
                dayoff = oadd(dayoff, (long)-1);
                if (--wday < 0) {
                    wday = LDAYSPERWEEK - 1;
                }
                --i;
            }
        }
        if (i < 0 || i >= len_months[isleap(y)][m]) {
            if (noise) {
                warning(_("rule goes past start/end of month--\
                    will not work with pre-2004 versions of zic"));
            }
        }
    }
    if (dayoff < min_time / SECSPERDAY) {
        return min_time;
    }
    if (dayoff > max_time / SECSPERDAY) {
        return max_time;
    }
    t = (zic_t)dayoff * SECSPERDAY;

    return tadd(t, rp->r_tod);
}

static void newabbr(const char* string)
{
    int i;

    if (strcmp(string, GRANDPARENTED) != 0) {
        const char* cp = NULL;
        char* wp = NULL;

        /*
         * Want one to ZIC_MAX_ABBR_LEN_WO_WARN alphabetics optionally
         * followed by a + or - and a number from 1 to 14.
         */
        cp = string;
        wp = NULL;
        while (isascii((unsigned char)*cp) && isalpha((unsigned char)*cp)) {
            ++cp;
        }
        if (cp - string == 0) {
            wp = _("time zone abbreviation lacks alphabetic at start");
        }
        if (noise != 0 && cp - string > 3) {
            wp = _("time zone abbreviation has more than 3 alphabetics");
        }
        if (cp - string > ZIC_MAX_ABBR_LEN_WO_WARN) {
            wp = _("time zone abbreviation has too many alphabetics");
        }
        if (wp == NULL && (*cp == '+' || *cp == '-')) {
            ++cp;
            if (isascii((unsigned char)*cp) && isdigit((unsigned char)*cp)) {
                if (*cp++ == '1' && *cp >= '0' && *cp <= '4') {
                    ++cp;
                }
            }
        }
        if (*cp != '\0') {
            wp = _("time zone abbreviation differs from POSIX standard");
        }
        if (wp != NULL) {
            wp = ecpyalloc(wp);
            wp = ecatalloc(wp, " (");
            wp = ecatalloc(wp, string);
            wp = ecatalloc(wp, ")");
            warning(wp);
            ifree(wp);
            wp = NULL;
        }
    }
    i = strlen(string) + 1;
    if (charcnt + i > TZ_MAX_CHARS) {
        error(_("too many, or too long, time zone abbreviations"));
        exit(EXIT_FAILURE);
    }
    (void)strcpy(&chars[charcnt], string);
    charcnt += eitol(i);
}

static int mkdirs(const char* argname)
{
    char* name = NULL;
    char* cp = NULL;

    if (argname == NULL || *argname == '\0') {
        return 0;
    }
    cp = name = ecpyalloc(argname);
    while ((cp = strchr(cp + 1, '/')) != NULL) {
        *cp = '\0';
#ifdef WIN32

        /*
         * DOS drive specifier?
         */
        if (isalpha((unsigned char)name[0]) && name[1] == ':' && name[2] == '\0') {
            *cp = '/';
            continue;
        }
#endif /* WIN32 */
        if (!itsdir(name)) {
            /*
             * It doesn't seem to exist, so we try to create it. Creation may
             * fail because of the directory being created by some other
             * multiprocessor, so we get to do extra checking.
             */
            if (mkdir(name, MKDIR_UMASK) != 0) {
                const char* e = gs_strerror(errno);

                if (errno != EEXIST || !itsdir(name)) {
                    (void)fprintf(stderr, _("%s: Cannot create directory %s: %s\n"), progname, name, e);
                    ifree(name);
                    name = NULL;
                    cp = NULL;
                    return -1;
                }
            }
        }
        *cp = '/';
    }
    ifree(name);
    name = NULL;
    return 0;
}

static long eitol(int i)
{
    long l;

    l = i;
    if ((i < 0 && l >= 0) || (i == 0 && l != 0) || (i > 0 && l <= 0)) {
        (void)fprintf(stderr, _("%s: %d did not sign extend correctly\n"), progname, i);
        exit(EXIT_FAILURE);
    }
    return l;
}

/*
 * UNIX was a registered trademark of The Open Group in 2003.
 */

#ifdef WIN32
/*
 * To run on win32
 */
int link(const char* oldpath, const char* newpath)
{
    if (!CopyFile(oldpath, newpath, FALSE)) {
        return -1;
    }
    return 0;
}
#endif

/*
 *	This allows zic to compile by just returning a dummy value.
 *	localtime.c references it, but no one uses it from zic.
 */
int pg_open_tzfile(const char* name, char* canonname)
{
    return -1;
}
